REVIEW: Mooshimeter, a compact wireless DMM

On the bench

The Mooshimeter comes in a sturdy, compact case along with three probe leads and three good-quality insulated crocodile clips. The instrument hardware is housed in a small transparent case. The only connectors on the case are the four test jacks: V (volts), A (amps), Ω (ohms), and C (common). The ohms jack can also be used for measuring low voltages under 1 V. There is no power switch on the case; the meter is constantly in standby mode. A blinking LED on the circuit board indicates the device status: slow blinking in standby mode, fast blinking when measurements are being made.

According to the manufacturer, the typical life of the two AA batteries in the meter is one year in standby mode and 50 hours in continuous use. That is reasonably long, and it’s easy to replace the batteries when they’re used up. However, for safety reasons you first have to loosen two screws to open the case.

I tested the Mooshimeter in the Elektor Castle together with a modern Android smartphone, because it needs at least Android 4.3 and support for Bluetooth 4.0 (BLE). Installing the app from Google Play was quick and easy, and the meter module was detected immediately after I opened the app. After I touched connectors icon next to the detected device, the connection was established and a screen appeared with two measurement values: current and voltage.

The screen presents an overview of all settings, including the current measurement range (set to autorange by default, but can also be set manually), the sampling rate (max. 8 kS/s per input, which is fairly high for a multimeter), and the size of the sample buffer. There is also a button for enabling or disabling data logging and a Zero button, which you can use to set the current readings as the reference points for subsequent measurements, which can be useful for making differential measurements. Overall the screen is well organized without any unnecessary extras, but at first it takes a little while to figure out what everything does. That’s because just about every box on the screen is a touchable control with several options. Although everything is very logically organized, you have to spend some time exploring the menu and trying out all the options. You can’t break anything, so simply touch every box and see what happens. After half an hour you know what everything does, and it’s nearly as easy as turning the selector knob on an ordinary DMM.

When you rotate the screen to horizontal orientation, you see a graphic display with trend curves of the measured voltage and current. You can also select X/Y display mode. In addition there is a buffer mode, and when you select this mode it shows the data in the buffer in the form of signal curves – a sort of mini oscilloscope screen. Processing the data took a good while on my quad-core smartphone, but that may be due to the Android OS. According to the Mooshim developers, some parts of the app work better on an iOS device.